These are… completely unrelated ratings?

The heat pump generates 162MWt, at the cost of around 50MWe.

The nuclear reactor produces 1.6GWe alongside 4.5GWt.

Furthermore the listed costs are also unrelated: the 235 millions are for the bare units (and an estimate for something a few years out), while the 8bn are turnkey (of what exactly I’m not sure: the beleaguered Olkiluoto 3 and flamanville 3 cost 11~12bn, while Taishan is estimated at under 8 for two reactors).

1.6GWe gives you 3.2GWt max alongside. In more modern this is even less. Of the 100% energy produced 33-38% will end up in the electric grid.

I'm just comparing the magnitudes here. A nuclear reactor powering dumb cheap resistive heaters is just several times more expensive than the heat pumps.

But unlike these heat pumps, the reactor doesn't need electricity.